中文摘要：

较之于陆地井架，浮式平台钻机井架在复杂海洋环境条件下还会受到平台运动引起的惯性载荷、重力的横向分力以及海洋风栽，井架在恶劣的海洋环境下保持稳定具有重要的意义。以南海某半潜式平台的运动为背景，研究配套的塔形井架在平面内的稳定性，通过定义等效抗弯刚度将空间变截面缀条格构式的井架等效为分段等截面实腹式悬臂梁，利用能量法建立井架平面内稳定性分析模型，对比理论结果和有限元数值结果验证理论模型的有效性。研究了顶驱和游车的位置对井架变形的影响，在最不利工况条件下研究了井架的整体稳定性。结果表明井架具有较好的平面内稳定性，在最大设计钩载以及强度范围内不会发生整体失稳。

英文摘要：

Compared to the land based derrick, the derrick of drilling rig in floating platform subjects to the inertial load caused by platform＇s motion, the transverse component of gravity and the ocean wind load in a complex marine environment. Remaining stable in a harsh marine environment is important to the derrick. Basing on the motion response of a semi-submerged platform in the South China Sea, in-plane stability of its matching tower derrick was investigated. Here the space latticed derrick with variable cross section was transformed into pieeewise solid cantilever beam with uniform cross section by defining equivalent bending rigidity. Then in-plane stability model of derrick was established by means of energy method. Theoretical result was compared with the numerical result to verify its validity. Effects of the top drive and the travel car＇s location on the derrick＇s deformation were investigated, and in-plane stability was also studied under the most dangerous working condition. It＇s found that the derrick satisfies the requirement of in- plane stability within the limits of maximum designed hook load and strength.